A key opposition party in the Democratic Republic of Congo has urged its supporters to boycott the voter registration process.

Thousand of people began queuing for their voting cards on Monday, but the Union for Democracy and Social Progress (UPDS) called it "a masquerade".

It criticised a parliamentary decision to postpone the election by six months.

The poll was due by 30 June under a 2002 deal to end a five-year civil war, but preparations were behind schedule.

Violence fears

The peace agreement helped set up a power-sharing government, which includes former rebel groups, but the UPDS is not part of the transitional administration.

We want the deadline to be respected or UDPS will call its militants to boycott electoral registration

Jean-Baptiste BumanzaUDPS spokesman

The party is led by veteran politician Etienne Tshisekedi, who headed the opposition under former dictator Mobutu Sese Seko.

"The UN representative a year ago stated no extension would be allowed to postpone the deadline at the end of transitional period on 30 June," UPDS spokesman Jean-Baptiste Bumanza told the BBC's French service.

"So we want the deadline to be respected or UPDS will call its militants to boycott electoral registration."

Earlier this year there were protests in the capital, Kinshasa, when a delay was first suggested.